1. Technical Field
One or more embodiments of the present invention are directed to a silicone-containing compound, an electrolyte for lithium secondary battery, a lithium secondary battery including the electrolyte, and a method of preparing the silicone-containing compound.
2. Related Art
Lithium secondary batteries are rechargeable at high rates and have energy densities that are about three times higher than conventional lead storage batteries, such as nickel-cadmium (Ni—Cd) batteries, nickel-hydrogen batteries, and nickel-zinc batteries. Thus, there has been increasing research and development intodirected to lithium secondary batteries.
In general, a lithium secondary battery includes a cathode, an anode, a separator disposed between the cathode and the anode, and an electrolyte. The electrolyte serves to transport lithium ions between the cathode and the anode.
These lithium ions may maintain charge neutrality by flowing together with electrons and may serve as media for storing electric energy in the electrodes. Accordingly, the amount of lithium ions intercalated into the electrode is important. Thus, to achieve high battery performance, an electrolyte with high ionic conductivity, high electrochemical stability, and high thermal stability is desired.
With the recent increasing demand for high-energy density lithium secondary batteries, for example, for use in electric vehicles, high-voltage electrode active materials have been used. By using a low-potential anode active material and a high-potential cathode active material, the range of electrochemical stability of the electrolyte may be narrower than the difference in potential between the anode and cathode active materials, and the lithium secondary may thus be more vulnerable to decomposition at the surface of the cathode and/or the anode, particularly at high temperatures. Lithium secondary batteries for electric vehicles and power storage systems are more likely to be exposed to high-temperature environments, and undergo rapid temperature increases from rapid charging and discharging. Such high-temperature environments may reduce the lifetime of batteries and the amount of energy stored therein.